well, where does that leave us? is it a combination of Visual Mod and some other mod, then?
essentially, it has been proven to me that this is caused by the VisualMod, as it is the ONLY mod i'm running that uses this method.
so, my guess is it's a specific version of the 4122 VisualMod, something akin to one version the Engine Mod which allows for the Iowa catapult to be used, and another version which breaks it.
did you actually check to see if a Betty got shot down in that mission, and also checked that you don't have 'no parachutes' option selected for them in FMB?
not really sure what to suggest. so far everything points to VisualMod, so there must be something different about your install that causes it not to happen.
as i mentioned earlier, i have ALWAYS used VisualMod, from the very first version to the most recent, and only encountered this problem recently for the first time - which leads me to think it's a specific version of the 4122 VisualMOd causing this.
i'm surprised that Pablo hasn't replied on this matter yet, I have mentioned it, and so far only silence. maybe he is just busy with the new Engine Mod atm...